The present invention relates to the manipulation and analysis of particles and, in particular, to a method suitable for manipulating and analyzing live bacterial cells.
The ability to manipulate and analyze nanoscale particles is potentially valuable in the assembly of nanoscale structures, for example, nanorods or nanotubes, into more complex structures. Such techniques could also prove useful in manipulating and analyzing single biological cells such as bacteria.
The manipulation of electrically polarizable particles within a poorly polarizable material (or poorly polarizable particles within a polarizable medium) can be accomplished by placing the particles in a spatially inhomogeneous electric field. In the case of polarizable particles, the field will induce equal and opposite charges on the particle. Unequal field strength will exist on each side of the particle because of the field inhomogeneity, producing a net dielectrophoretic force that pulls the particle toward the greater field concentration.
Such techniques have been used to trap particles and cells at electrodes by drawing the particles and cells to the electrode, or to hold cells within a cage formed of symmetrically balanced electrodes that repel the cell.
While such techniques allow the capture of extremely small particles in a liquid, the ability to precisely control the movement of constrained particles or cells is relatively limited.